: Why do the VHS camcorder footages look so silky smooth , almost like 60fps ?

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This is a question that has been at back of mind for the past 6 months, I’ve searched a lot but never once I did get a comprehensive answer to the question.

I would like it very much if someone explain me the exact reason why is it so?

In: Technology
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Analog films has an analog motion blur. The motion blur is exact and true to nature, and very similar to what our eyes perceive. This is hard to replicate in for example games, where calculating motion blur exactly is difficult in such a short time, and would increase processing power significantly.

Great question! VHS is and interlaced format, where every other line of a frame is shown, and then the opposite lines. This makes 30 completes frames, but 60 refreshes. Your TV (or the digitization process) de-interlaces the signal from an analog source like VHS. Meaning, it will double every line in every frame, giving you exactly 60 full frames per second.

If the VHS recording use NTSC you are at 60 fields per second or 50 fields per second for PAL

It is not frames per second because they are interlaced so the framer rate of NTSC is 30 frames per second where each frame is made of two interlaced fields with half the resolution at 60 fields per second.

The interlacing is there to make motions smoother and to reduce flicker.

Because it *is* 60 fps. Just not *frames* per second, just *fields* per second. It still means the scene is recorded 60 times a second, just not every line of it. Back in the age of tube screens, that created a great compromise between motion clarity and resolution, which is sadly lost with flat-panel displays where interlacing creates nasty visible artifacts.

On the other hand, low refresh rates in CRTs would cause one hell of a flicker, so 30 frames per second progressive scan were out of the question.

In film and digital video, we typically have each entire “frame” of footage recorded all in one piece and displayed all in one piece. 24 fps and 30 fps are pretty common.

On old analog TVs and video tapes, the picture was divided into horizontal lines, and only half of the image was recorded/drawn at a time… e.g., only the odd lines, and then only the even lines. These separate sets of lines that compose the frame are called “fields”. 60 *fields* per second was a pretty typical rate.

So basically, VHS/TV trades some vertical resolution for better fps.